The present disclosure relates generally to refrigeration systems for galleys of aircraft and, more particularly, to valve control systems for refrigeration systems.
Airline meals are typically prepared in advance by caterers. In one approach, a caterer prepares a large quantity of individual meals and stores the meals in a refrigeration locker. In preparation for a flight, the caterer takes the required quantity of meals out of the locker and places the meals in aircraft galley carts. The caterer then transports the galley carts to the aircraft and loads the meals into a galley. The galley typically includes a plurality of refrigerated compartments or zones. Accordingly, one or more galley carts may be loaded into a single compartment.
In operation, conventional galleys typically includes a single refrigeration unit that supplies cooled air to each of the compartments or zones via a plurality of ducts. Proposals have been made for galleys to include valves and a valve control system for controlling airflow to individual galley carts to direct specific airflow to needed galley carts at any time. For example, valve control systems have been proposed that allow closing off airflow to empty galley carts or to direct higher airflow to galley carts that need to be cooled quickly, such as galley carts that recently arrived on the aircraft. The valve control system adds complexity to the refrigeration system Moreover, if the valve control for one of the valves faults or fails such that the refrigeration system is unable to cool one of the galley carts, such failure can lead to flight departure delays or cancelled flights to repair the valve control.